Detection of the damage caused to DNA by a thiophene-S-oxide using an electrochemical DNA-biosensor

• Autor(a) principal: Brett, Ana Maria Oliveira
• Data de Publicação: 2003
• Outros Autores: Silva, Luis Antônio da, Fujii, Hideki, Mataka, Shuntaro, Thiemann, Thies
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10316/5160; https://doi.org/10.1016/S0022-0728(03)00245-6
• topic: Thiophene-S-oxide; DNA-biosensor; Oxidative damage; 8-Oxoguanine; Voltammetry; Electrochemistry; Oxidation; Reduction; DNA-electrochemical biosensors

The electrochemistry of 3,4-dibenzyl-2,5-dimethylthiophene-S-oxide was investigated as well as its interaction with dsDNA. The electrochemical study of the thiophene-S-oxide was performed at different pH values, in a mixed solvent and by solid state voltammetry, and showed that the molecule is reduced at a very negative potential, and the reduction is pH dependent. A glassy carbon electrode modified with a thick thiophene-S-oxide+dsDNA mixture was used to study the interaction of thiophene-S-oxide in situ with dsDNA at a charged interface. The experimental results give strong evidence that the reduced thiophene-S-oxide interacts with dsDNA causing damage with possible strand break and that the thiophene-S-oxide adduct formed with dsDNA can still undergo reduction.